Optical tomographic imaging apparatus

Patent metadata

Field	Value
Publication number	US-9299134-B2
Application number	US-201113575730-A
Country	US
Kind code	B2
Filing date	Mar 18, 2011
Priority date	Mar 25, 2010
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

Provided is an optical tomographic imaging apparatus including: a unit for creating a measuring beam and a reference beam from beam of a light source, and generating interference light by combining a return beam resulting from the measuring beam and the reference beam; a unit for detecting the interference light to generate a detection signal; a unit for forming an image of the object based on the detection signal; a unit for designating a specific area in the image; a unit for setting a calculation index and a determination reference range used for determining image quality of the specific area; and a unit for applying calculation processing to a luminance value of the specific area based on the calculation index, determining whether a calculated value obtained as a result of the calculation processing is within the determination reference range, and outputting a detection result.

First claim

The invention claimed is:

1. An optical tomographic imaging apparatus comprising:
a processor and a memory, cooperating to function as units comprising:
(a) an image forming unit configured to form a tomographic image of an object based on an interference light generated by a measuring light which has passed through the object and a reference light which has passed through a reference optical path;
(b) an image display unit configured to display the tomographic image on a display device;
(c) an area setting unit configured to set, based on a user's operation, first and second partial areas within the tomographic image displayed on the display device;
(d) an image quality obtaining unit configured to obtain an image quality of an image of the second partial area as an image quality of the tomographic image, based on first values in the first partial area and second values in the second partial area, the first values in the first partial area being used as a reference value for calculating the image quality of the image of the second partial area;
(e) a determination unit configured to determine whether a value indicating the image quality obtained by the image quality obtaining unit satisfies a specific determination reference;
(f) an output unit configured to display, on the display device, a result of a determination of the determination unit; and
(g) a control unit configured to control at least one of an amount of the measuring light for the object, a spectral shape of the measuring light, a polarization state of the measuring light, an incident position of the measuring light, and an optical path of the reference light, in accordance with the result of the determination,
wherein the image forming unit forms a new tomographic image based on the controlling by the control unit.

2. An optical tomographic imaging apparatus according to claim 1 , wherein the output unit displays on the display device, together with the result of the determination, the value indicating the image quality.

3. An optical tomographic imaging apparatus according to claim 1 , wherein the control unit is configured to control the amount of the measuring light for the object, in accordance with the result of the determination.

4. An optical tomographic imaging apparatus according to claim 3 , wherein the memory stores the result of the determination and a controlled position of a reference object on the reference optical path, which is directed to the result of the determination, and
wherein the control unit selects the image obtained at the controlled position satisfying the determination reference, and causes the memory to store the image obtained at the controlled position satisfying the determination reference.

5. An optical tomographic imaging apparatus according to claim 1 , wherein the processor and the memory further cooperate to function as a setting unit configured to set a kind of the value indicating the image quality, and the specific determination reference, based on a user's operation.

6. An optical tomographic imaging apparatus according to claim 5 , wherein the setting unit sets the kind of the value designating the image quality and the specific determination reference, in accordance with the first partial area and the second partial area which have been set by the area setting unit.

7. An optical tomographic imaging apparatus according to claim 5 , wherein the setting unit sets an area within the tomographic image based on a name of a specific portion selected by a user, and
wherein the setting unit sets the kind of the value indicating the image quality and the specific determination reference, in accordance with the name which has been selected by the user.

8. An optical tomographic imaging apparatus according to claim 5 , wherein the setting unit sets the specific determination reference in accordance with the kind of the value indicating the image quality, which has been set by the setting unit.

9. An optical tomographic imaging apparatus according to claim 1 , wherein the image quality obtaining unit obtains the image quality based on one of (a) a ratio of standard deviation of luminance values in the first partial area and a maximum of luminance values in the second partial area, and (b) a value calculated based on the ratio.

10. An optical tomographic imaging apparatus according to claim 1 , wherein the image quality obtaining unit obtains the image quality and uses, as the value indicating the image quality, any one of (a) calculated values calculated by any one of equations of:
A1/A2;
|A1−A2|/(A1+A2); and

|A1−A2|/√(δ1^2−δ2^2),

where A 1 and δ 1 respectively denote an average value and a standard deviation of luminance values in the first partial area, and A 2 and δ 2 respectively denote an average value and a standard deviation of luminance values in the second partial area, and (b) a value calculated based on the calculated value.

11. An optical tomographic imaging apparatus according to claim 10 , wherein the equation A 1 /A 2 is used.

12. An optical tomographic imaging apparatus according to claim 10 , wherein the equation |A 1 −A 2 |/(A 1 +A 2 ) is used.

13. An optical tomographic imaging apparatus according to claim 10 , wherein the equation |A 1 −A 2 |√(δ 1 ^2−δ 2 ^2) is used.

14. An optical tomographic imaging apparatus according to claim 1 , wherein the processor and the memory further cooperate to function as an image selection unit configured to select the tomographic image based on the result of the determination of the determination unit.

15. An optical tomographic imaging apparatus according to claim 1 , further comprising a light source.

16. An optical tomographic imaging apparatus according to claim 1 , wherein after the image forming unit forms the new tomographic image, the operations of (b) through (g) are performed using the new tomographic image.

17. An optical tomographic imaging method using an optical tomographic imaging apparatus, which apparatus includes a processor coupled to a memory, the method comprising the steps of:
(a) forming a tomographic image of an object based on an interference light generated by a measuring light which has passed through the object and a reference light which has passed through a reference optical path;
(b) displaying the tomographic image on a display device;
(c) setting, based on a user's operation, first and second partial areas within the tomographic image displayed on the display device;
(d) obtaining an image quality of an image of the second partial area as an image quality of the tomographic image, based on first values in the first partial area and second values in the second partial area, the first values in the first partial area being used as a reference value for calculating the image quality of the image of the second partial area;
(e) determining whether a value indicating the image quality obtained in the image quality obtaining step satisfies a specific determination reference;
(f) displaying, on the display device, a result of a determination in the determination step; and
(g) controlling at least one of an amount of the measuring light for the object, a spectral shape of the measuring light, a polarization state of the measuring light, an incident position of the measuring light, and an optical path of the reference light, in accordance with the result of the determination,
wherein a new tomographic image is formed based on the controlling by the controlling step.

18. A non-transitory medium having a program recorded thereon, for controlling a compu

Assignees

• Yuasa Takashi
• Canon Kk

Inventors

• Yuasa Takashi

Classifications

• G06T2207/30168

  Image quality inspection · CPC title

• G06T2207/10101

  Optical tomography; Optical coherence tomography [OCT] · CPC title

• G06T7/0002 Primary

  Inspection of images, e.g. flaw detection · CPC title

• A61B5/0066

  Optical coherence imaging · CPC title

• A61B3/102

  for optical coherence tomography [OCT] · CPC title